const promise1 = new Promise((resolve, reject) => reject());
const promise2 = promise1.then(
  null,
  function () {
    return 123
  }
)

promise2.then(
  (rsp) => { console.log('promise2 已完成' + rsp)},
  (err) => console.log('promise2 已拒绝' + err)
)